TSQL Convert rows to columns - sql

Question

I have a query that returns some data that looks like this:
Description
----------
Thing1
Thing2
Thing3
Thing4
Thing5
Thing6
Thing7
I would like to make the data look like this:
Desc1 Desc2 Desc3
----- ----- -----
Thing1 Thing2 Thing3
Thing4 Thing5 Thing6
Thing7
Could someone provide an example on how to do this?
Thanks!

Answer 1

You stated the comments that the order of the data in the Desc columns does not matter.
If that is the case, then you can use the following which implement NTILE and row_number():
;with cte as
(
select description,
'desc'+cast(ntile(3) over(order by Description) as varchar(10)) col
from yt
)
select desc1, desc2, desc3
from
(
select description, col,
row_number() over(partition by col order by col) rn
from cte
) d
pivot
(
max(description)
for col in (desc1, desc2, desc3)
) piv;
See SQL Fiddle with Demo.
The NTILE function distributes the rows into separate groups. Once that is done, then apply a row_number() to give a unique number to each row while grouping.
This gives a result:
| DESC1 | DESC2 | DESC3 |
----------------------------
| Thing1 | Thing4 | Thing6 |
| Thing2 | Thing5 | Thing7 |
| Thing3 | (null) | (null) |

Answer 2

Another approach of doing it, if the order does matter, and skipping PIVOT function:
WITH CTE AS
(
SELECT
(ROW_NUMBER() OVER (ORDER BY [Description])+2) /3 AS RowID,
(ROW_NUMBER() OVER (ORDER BY [Description])+2) % 3 +1 AS ColID,
[Description]
FROM Table1
)
SELECT
MIN(CASE WHEN ColID = 1 THEN [Description] END) DESC1
,MIN(CASE WHEN ColID = 2 THEN [Description] END) DESC2
,MIN(CASE WHEN ColID = 3 THEN [Description] END) DESC3
FROM CTE
GROUP BY RowID
SQLFiddle DEMO

Answer 3

I used the base data from the sqlfiddle of #NenadZivkovic to provide a different solution
http://www.sqlfiddle.com/#!6/b676a/15
WITH Numbered AS
(
SELECT
ROW_NUMBER() OVER (ORDER BY Description) as rn,
(ROW_NUMBER() OVER (ORDER BY Description) - 1) % 3 as colid,
(ROW_NUMBER() OVER (ORDER BY Description) - 1) / 3 as line,
Description
FROM Table1
)
SELECT desc1.description as DESC1, desc2.description as DESC2, desc3.description as DESC3
FROM (SELECT line, description FROM Numbered WHERE colid=0) as desc1
LEFT JOIN
(SELECT line, description FROM Numbered WHERE colid=1) as desc2
ON (desc1.line = desc2.line)
LEFT JOIN
(SELECT line, description FROM Numbered WHERE colid=2) as desc3
ON (desc2.line = desc3.line)